Valve bushing



Sept. 15, 1925. 1,554,004

C. C. HANSEN VALVE BUSHING Filed March 13. 1925 INVENTOR "ma)' esCHZmJe/z HIS ATTORN Patented Sept. 15, 1925.

UNITED STATES PATENT OFFICE...

CHARLES C. HANSEN, OF EASTON, PENNSYLVANIA, ASSIGNOR TO INGERSOLL-RANDCOMPANY, OF JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY.

vALvE BUSHING.

To all whom it may concern..-

Be it known that I, CHARLES C. HANsnN,

a citizen of the United States, and a resident of Easton, in the countyof Northampton and State of Pennsylvania, have invented a certain Valve.Bushing, of which the following is a specification accompanied bydrawings.

This invention relates to fluid actuated rock drills of the hammer type,but more particularly to the construction of the valve chest andbushings for the motive fluid distributing valve.

One object of the invention is to enable both bushings to be insertedthrough only one end of the valve chest. Another object is to insureproper insertion of the bushings, and a still further object is tosecure the bushings against longitudinal and rotative movement withinthe chest.

Other objects and advantages of the invention will be in part obviousand in part pointed out hereinafter.

In the drawings forming part of the specification and in which similarreference characters refer to similar parts,

Figure 1 is a longitudinal sectional elevation of so much of a rockdrill as will serve to illustrate the invention,

Figure 2 is a perspective view of a valve bushing adapted to be used inone end of the chest, and

Figure 3 is a perspective view of a bushof the valve chest.

Referring to the drawings, the invention is shown embodied in a rockdrill of the drifter type having a cylinder A, in which a hammer pistonB reciprocates. A front cylinder washer C forms a closure for one end ofthe cylinder and is provided with a suitable bore to receive the shankof the piston B. The opposite end of the cylinder A is closed by a backcylinder washer D which also serves to centralize a back head E.

Disposed within the back head E is a rotation ratchet F, having ratchetteeth F. A rifle bar G engages the piston B in the usual manner and isprovided with a head H carrying a plurality of pawls J. The pawls J areso arranged that they Will permit the ing adapted to be used in theopposite end Application filed March 13, 1925. Serial No. 15,192.

rifle bar to rotate in one direction when the piston moves on theforwardstroke, but on the return stroke of the piston the pawls willengage the teeth F and hold the rifle bar against rotation, therebyimparting a rotary movement to the piston.

In this instance, a valve chest K is formed integral with a cylinder A,and motive fluid admitted through a passage K is distributed by a spoolvalve L having a central flange O and end flanges P and Q. The valvechest K is provided with a bore R to receive a pair of bushings S and T.

The bushings S and T provide a seat for i the valve L and thus protectthe chest against wear due to the reciprocatory movement of the valve.

In accordance with the practice of the invention, only one end of thebore R is adapted to receive the bushings S and T, and suitable meansare provided to insure the proper insertion of the bushings in therespective ends of the chest for which they are designed. To this end, ascrew threaded plug U is formed eccentrically on an end of the bushing Sand is adapted to extend through a suitable hole V in the end wall ofthe chest K. A nut IV screwed on the plug U holds the bushing S againstlongitudinal movement within the chest.

In like manner, the bushing T is provided on one end with aneccentrically arranged projection X which cooperates with a recess Y inthe back head E to hold the bushing T against rotation in the chest. Thebushing T is also provided with a flange Z which extends into a suitablebore 6 in the end of the chest K. This flange serves as a stop for thebushing T in one direction, and being larger than the bore R of thechest also prevents the bushing T from being inserted in the oppositeend of the chest. The projection Y is preferably provided with aninternally screw threaded recess 0 to receive the end of a bolt or othersimilar implement for the purpose of withdrawing the bushing from thechest.

A suitable space is provided between the inner ends 0Z and c of thebushings S and T respectively to receive the central flange O of thevalve L and permit reciprocation of the valve. In this instance theinner ends of the bushings serve as stops for limiting the movement ofthe valve in opposite direction's.

This invention is particularly applicable to machines wherein it is notconvenient to have opposed ports and passages having similar functionscommunicate with the valve chest at corresponding points. This is Welllllustrated 1n Flgure 1 in which a passage f formed in thebottom of thebush-' distributing valve in said chest, a pair of dissimilar bushingsforming a seat for said valve and lnsertable from one end of the chest,pro ect1'ons arranged eccentrlcally on said bushings one of saidprojections being cooperative; with said chest to insure properinsertion of the bushings in the chest and to hold the bushings againstrotation, and a back head for the cylinder cooperating to hold one ofthe bushings in place. v

2. In a fluid actuated rock drill, the combination of a cylinder and avalve chest having a bore and a hole in oneenld arranged eccentricallywith respect to'th'bore, a back head for the cylinder provided with a recess eccentric to the valve chest bore, a distributing valve in saidchest, a pair of dissimilar removable bushings forming a seat for saidvalve and insertable from one end of said chzst, an internally threadedeccentrically arranged projection on one of said bushings to cooperatewith the recess in the back head for holding the bushing againstrotation, an externally threaded eccentrically arranged plug on theother said bushing to cooperate With the hole in the end of the chestfor holding the bushing against rotation, and means for holding thebushings against longitudinal movement.

In testimony whereof I have signed this specification.

oHARILEs o. rrilNsnN.

